Morphological Alteration and Reduction of MAP2-immunoreactivity in Pyramidal Neurons of Cerebral Cortex in a Rat Model of Focal Cortical Compression.

MedLine Citation:

PMID:
21401443
Owner:
NLM
Status:
Publisher

Abstract/OtherAbstract:

Subdural hematoma causes cortical damage including brain tissue disruption, often resulting in neuronal dysfunction and neurological impairment. The aim of the present study was to identify the relationship between cerebral compression and neuronal injury. In this report, we investigated time-dependent morphological alterations within layers II, III, and V pyramidal neurons in the cerebral cortex, using Golgi-Cox staining and immunohistochemistry for microtubule-associated protein 2 (MAP2) in a rat model of focal cortical compression. An acryl pole was used to experimentally induce chronic cerebral compression by continuous pressure onto the cortical surface. Changes in cellular morphology were examined at five survival time periods: 12 h and 1, 2, 3, and 4 w. The Golgi-Cox method revealed time-dependent alterations in dendritic length of apical and basilar dendrites of pyramidal neurons. The number of dendritic branch segments and spines of basilar dendrites decreased in cells in layers II, III and V. Immunohistochemical staining for MAP2 revealed changes in the intracellular distribution of immunoreactive materials. A significant reduction in MAP2 immunostaining was found in nerve cell bodies and apical dendrites of ipsilateral cortical neurons. The number of MAP2-immunoreactive neurons was significantly decreased at 12 h compared with the contralateral cerebral cortex in the same animal. Dendritic changes in layers II, III and V pyramidal neurons were accompanied by reductions in intracellular MAP2-immunoreactive materials. The present results suggest that cortical compression causes alteration of cellular morphology as a consequence of injury and these morphological changes may be related to reductions in MAP2-immunoreactive materials.